This is a continuation of international application PCT/EP02/08188, which was published in French on Feb. 20, 2003, as international publication WO 03/014208 and which claims priority of French application 01/10479 filed Aug. 3, 2001.
The present invention relates to elastomer compositions obtained by deposition and drying of an aqueous dispersion containing at least latex, a filler and conventional vulcanization ingredients, and by vulcanization under pressure.
Since the very beginning of the 20th century, carbon black has been the dominant filler for rubber mixtures conventionally used in the tire industry due to the outstanding reinforcing properties which it imparts to the mixtures. Such reinforcement brings about a change in the uncured and cured properties of the mixture. The presence of a filler in particular results                when uncured:—in an increase in viscosity,        when cured:—in an increase in resistance to any deformation,         —in a major increase in hysteresis,         —in an improvement of limit values and wear resistance.        
Patent application FR 2 588 008 proposes, in order to obtain a filler-polymer composition from latex, impregnating the filler with at least one latex emulsion in such a manner as to bring about at least partial coagulation of the latex polymer by dehydration of the latex. The content of dry polymer relative to the filler varies between 25 and 100%. Silane may be added in the form of an aqueous emulsion. Masterbatches produced in said manner disperse the filler more effectively.
However, the enhanced mechanical properties of an elastomer composition obtained from elastomers and fillers processed in the solid phase in internal mixers or roll mills are generally attributed to the significant mechanical working imparted to the mixture during the production thereof The very nature of a latex makes it possible to dispense with required significant mechanical working in order to mix a filler and a latex. It would seem, however, that filler-polymer compositions which have adequate mechanical properties for use in a tire have never been obtained in this manner.
The object of the invention is to be able to gain the advantage of the reduced energy consumption associated with the production of latex-based filler-polymer compositions while obtaining the adequate mechanical properties of compositions as they are conventionally produced in the tire industry.